The standard model (SM) of particle physics includes a number of uncharged long-lived particles (LLP) such as neutrinos, neutrons or neutral B, D, and K mesons. Exotic, but so far undetected long-lived particles emerge in many theories extending the standard model. We focus on detecting such neutral particles and present selected recent results of searches by the ATLAS and CMS collaborations [1]}, [2]} at the LHC in proton-proton collisions at a centre-of-mass energy of \(\sqrt{s} = 13\)  TeV.
In the context of these searches LLP's are defined as particles that do not decay instantly at the interaction point, where they are produced, but at some measurable distance within the detector. They may also remain stable within the detector volume.
